every great once in awhile I get a screech from the starter when engaged
 

I have noticed this twice on my '87 SDL. I'll get in and flip the key to start it but it makes the kind of noise a car makes when you engage the starter and it's already running? No, the car is not running in my case but it sounds like it is when the starter's used. The car takes no time at all to start once cranking but I stop as soon as I hear that noise, which is as soon as the starter is engaged. Then when I retry it it works fine. What do you guys think? Could something be amiss with the starter or could the flywheel have broken teeth?

Thanks
David

That is definitly interesting- I have had a similar issue with mine. Not so much anymore as it used to over the first year I had the car, the starter would "squeal" after starting the engine about 80% of the time. I was going to just replace the starter but it hasn't done it in months now so I'll just leave it alone.

Mine doesn't squeal after the engine's been started but in place of starting it squeals.

Thanks
David

Just my two cents worth. Possibly dry starter bearings and other parts. Or perhaps combination of wear and no additional lube for 20 years or more. Know good sleeve bearings designed in phosphor sintered bronze to retain lubricant as material is porus but some of our starters have not been lubed in almost thirty years now. Good periodic maintenance project perhaps. :) Why not pull and replace any worn parts plus lube and change brushes and true armature if required. Gotta be cheaper than the eventual replacement of everything when that armature starts dragging. On the otherhand may only need cleaning and relube with maybe the change of a couple of cheap bearings at most.

It sounds like you have a broken tooth or two on your flywheel :(

When that spot happens to stop at the starter pinion it screaches until it moves enough to engage a good tooth. You'll know it is this because eventually enough teeth will be missing that the car will no longer start at all and will just screach. It's a classic symptom not just for diesels but for all cars.

A mechanic can usually remove the starter and have someone manually turn the crankshaft and look at the flywheel as it goes around to find the broken tooth or teeth. Unfortunately, if they see broken teeth it is a big job to repair because you have to replace the flywheel.

On some cars the distance between the starter and flywheel is adjustable either with shims or a slot, so maybe this is all that is wrong, but I don't know if MB makes this adjustable or not.

There is also a problem with just simply the starter not quite lining up to the gear on the flyweel. When you hear your screech the drive isn't engaging into the teeth of the flywheel but instead its buzzing on the surface of it since it didn't quite line up properly. Might be worth pulling the starter, when you have time, and have a look see. The broken tooth idea isn't a bad one however if there was a broken tooth it wouldn't nessisarily start every time after the first buzz. I'd stick with the simple and work your way up :)

You need to pull your starter out and look at the gear on it. Odds are it's chewed up. Don't know on an MB starter but a US starter you can get a new bendix with a new gear on it for about $10. If you replace the gear and it's still doing it then you've got some broken teeth on the ring gear of the flexplate or flywheel whichever you have. If it's a flywheel(manual trans) you can get new ring gear pressed on. If you have a flexplate you'll need to get the whole thing new. In any case if a new gear on the starter doesn't fix it you'll need to pull the trans.

Two problems may be at issue in early part of this thread. There is a squeel sound unlike clashing metal described as well as a clashing of metals screech sound as well depending on the post read. :)

You don't have to get a ring pressed on. Just put flywheel in the freezer and the new ring gear in the oven at about 400*F and the ring gear will drop on the flywheel.

P E H

If you have a broken tooth on the flywheel you should be able to hear it again when it makes a full revolution. Try cranking immediately the next time you start it cold (allow no time for glow) to try to get a full revolution before starting. If it cranks without a crunch or grind sound within about 5-10 seconds your flywheel teeth are probably OK. The problem then can be isloated to the starter. If the bendix gear is getting tired it will make the sounds you describe.

I think it is the bendix gear as you guys describe. I have to pull the starter next week when I do the rear crank seal so I'll see what I have. It did it again today and I don't want to let it go too long so as to tear up the teeth on the flywheel.

Thanks
David

Our 83 was making an odd noise after starting for a while, but it has since stopped now that its warmer, it only does it if you did a short-crank in cold weather, with a longer crank time it also didn't do it....now that its gone, we're not concerned.... :D

The noise I'm speaking of occurs when the key is first put to the crank position. It doesn't do it after the car's been started.

Thanks
David

This may sound far fetched, but when you hear the screetch do you have the radio on? On my 87 300d I am getting electrical noise feedback from the starter into the radio. Easy to check.
Oily